U.S. patent number 5,258,477 [Application Number 07/598,565] was granted by the patent office on 1993-11-02 for monomers and polymers containing acetal and aldehyde groups.
This patent grant is currently assigned to National Starch and Chemical Investment Holding Corporation. Invention is credited to Robert L. Billmers, Rama S. Chandran, Patrick G. Jobe, Paul R. Mudge, Michael T. Sarkis, John J. Tsai.
United States Patent |
5,258,477 |
Tsai , et al. |
November 2, 1993 |
**Please see images for:
( Certificate of Correction ) ** |
Monomers and polymers containing acetal and aldehyde groups
Abstract
Various novel acetal- and aldehyde-containing monomers are
prepared. They can be polymerized and copolymerized by conventional
polymerization techniques. The polymers contain repeating units
derived from one or more ethylenically or allylically unsaturated
monomers containing an acetal group or aldehyde group and
optionally one or more repeating units derived from ethylenically
or allylically unsaturated monomers other than the
acetal-containing or aldehyde-containing monomer such as ethylene,
vinyl acetate, ethyl acrylate, butyl acrylate, 2-ethylhexyl
acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, methyl
methacrylate or acrylic acid. Aqueous emulsions of polymers
containing the acetal-containing monomers and a hydroxy-containing
monomer are useful as binders for nonwoven fabrics.
Inventors: |
Tsai; John J. (Belle Mead,
NJ), Jobe; Patrick G. (Westfield, NJ), Billmers; Robert
L. (Stockton, NJ), Chandran; Rama S. (South Bound Brook,
NJ), Mudge; Paul R. (Belle Mead, NJ), Sarkis; Michael
T. (Lawrenceville, NJ) |
Assignee: |
National Starch and Chemical
Investment Holding Corporation (Bridgewater, NJ)
|
Family
ID: |
27021392 |
Appl.
No.: |
07/598,565 |
Filed: |
October 16, 1990 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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411440 |
Sep 22, 1989 |
|
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Current U.S.
Class: |
526/315; 526/266;
526/270; 560/224; 560/222; 560/198; 549/495; 549/483; 549/502;
549/501; 549/454; 549/375; 526/307.5; 526/304; 564/292 |
Current CPC
Class: |
C07C
69/60 (20130101); C08F 222/20 (20130101); C08F
222/205 (20200201); C08F 220/28 (20130101); C08F
220/282 (20200201) |
Current International
Class: |
C08F
220/28 (20060101); C07C 69/00 (20060101); C07C
69/60 (20060101); C08F 222/00 (20060101); C08F
222/20 (20060101); C08F 220/00 (20060101); C08F
016/34 (); C07D 319/06 (); C07C 069/34 (); C07C
213/00 () |
Field of
Search: |
;526/315,266,270,304,307.5 ;549/375,454,501,502,483,495
;560/198,222,224 ;564/292 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Abstract from World Patents Index of West German Offenlegunschrift
No. DE-OS 2,757,206. .
Abstract from World Patents Index of U.S. Pat. No.
4,605,781..
|
Primary Examiner: Michl; Paul R.
Assistant Examiner: Niland; P.
Attorney, Agent or Firm: Kelley; Margaret B. Szala; Edwin
M.
Parent Case Text
This is a continuation of co-pending application Ser. No. 411,440,
filed on Sep. 22, 1989, now abandoned.
Claims
What is claimed is:
1. An acetal-containing monomer selected from the group consisting
of (3,3-dimethoxy-2,2-dimethyl)propyl crotonate,
(3,3-dimethoxy-2,2-dimethyl)propyl fumarate,
(3,3-dimethoxy-2,2-dimethyl)propyl maleate,
(3,3-dimethoxy-2,2-dimethyl)propyl itaconate,
bis(3,3-dimethoxy-2,2-dimethyl)propyl fumarate,
bis(3,3-dimethoxy-2,2-dimethyl)propyl maleate, and
bis(3,3-dimethoxy-2,2-dimethyl) propyl itaconate.
2. A polymer comprising an ethylenically unsaturated monomer and an
acetal-containing monomer selected from the group consisting of
(3,3-dimethoxy-2,2-dimethyl)propyl crotonate;
(3,3-dimethoxy-2,2-dimethyl)propyl fumarate;
(3,3-dimethoxy-2,2-dimethyl)propyl maleate;
(3,3-dimethoxy-2,2-dimethyl)propyl itaconate;
bis-(3,3-dimethoxy-2,2-dimethyl)propyl fumarate;
bis(3,3-dimethoxy-2,2-dimethyl)propyl maleate;
bis(3,3-dimethoxy-2,2-dimethyl)propyl itaconate;
[5-(dimethoxymethyl)furfur-2-yl]methyl acrylate;
5-(N,N-di[propyl-1-en-3]amino-methyl)-2-dimethoxymethyl furan;
2-(dimethoxymethylphenoxy)ethyl acrylate;
2-(2-[2-(1,3-dioxolano)]phenoxy)ethyl acrylate;
2-hydroxy-3-(4-dimethoxymethylphenoxy)propyl methacrylate; and
2-hydroxy-3-(2-dimethoxymethyl phenoxy)propyl methacrylate.
3. A monomer containing aromatic acetal groups selected from the
group consisting of [5-(dimethoxymethyl)furfur-2-yl]methyl
acrylate,
5-(N,N-di-[n-propyl-1-en-3-yl]aminomethyl)-2-dimethoxymethyl furan,
5-(n-propyl-1-en-3-oxymethyl)-2-dimethoxymethyl furan, and
5-(n-propyl-1-en-3-aminomethyl)-2-dimethoxymethyl furan.
4. A monomer containing aromatic acetal groups which is selected
from the group consisting of 2-(2-dimethoxymethyl-phenoxy)ethyl
acrylate, 2-(2-(2-(1,3-dioxalano)phenoxy)ethyl acrylate,
2-hydroxy-3-(4-dimethoxymethylphenoxy)propyl methacrylate, and
2-hydroxyl-3-(2-dimethoxymethyl-phenoxy)propyl methacrylate.
5. The polymer of claim 2, wherein the alkyl acrylate is ethyl
acrylate or butyl acrylate; wherein the alkyl methacrylate is
methyl methacrylate; wherein the hydroxyalkyl acrylate is
2-hydroxyethyl acrylate or 2-hydroxypropyl acrylate; wherein the
vinyl ester is vinyl acetate; wherein the acetal-containing monomer
is selected from the group consisting of
[5-(dimethoxymethyl)furfur-2-yl]methyl acrylate,
[5-(dimethoxymethyl)furfur-2-yl]methyl methacrylate,
5-(N,N-di-[propyl-1-en-3-]aminoethyl)-2-dimethoxymethyl furan,
(3,3-dimethoxy-2,2-dimethyl)propyl crotonate,
(3,3-dimethoxy-2,2-dimethyl)propyl maleate,
bis(3,3-dimethoxy-2,2-dimethyl)propyl itaconate,
bis(3,3-dimethoxy-2,2-dimethyl)propyl fumarate,
bis(3,3-dimethoxy-2,2-dimethyl) propyl maleate,
2-(2-dimethoxymethylphenoxy)ethyl acrylate,
2-hydroxy-3-(4-dimethoxymethylphenoxy)propyl methacrylate,
2-hydroxy-3-(2- dimethoxymethylphenoxy)propyl methacrylate,
bis(3,3-dimethoxy- 2,2-dimethyl)propyl crotonate, and
(3,3,-dimethoxy-2,2,-dimethyl)propyl itaconate.
6. The polymer of claim 2, wherein the ethylenically unsaturated
monomers are a hydroxyalkyl acrylate or methacrylate and an alkyl
acrylate or methacrylate; or wherein the ethylenically unsaturated
monomers are a hydroxyalkyl acrylate or methacrylate, ethylene, and
a vinyl ester; or wherein the ethylenically unsaturated monomers
are a hydroxyalkyl acrylate or methacrylate and styrene and/or
acrylonitrile and an alkyl acrylate of methacrylate.
7. An aqueous emulsion, adapted for producing non-wovens,
containing the polymer of claim 5.
8. The monomer of claim 3, wherein the monomer is
[5-(dimethoxymethyl)furfur-2-yl]methyl acrylate.
9. The monomer of claim 3, wherein the monomer is
5-(N,N-di-[n-propyl-1-en-3-yl]aminomethyl)-2-dimethoxymethyl
furan.
10. The monomer of claim 4, wherein the monomer is
2-(2-dimethoxymethylphenoxy)ethyl acrylate.
Description
BACKGROUND OF THE INVENTION
This invention relates to novel acetal-containing and
aldehyde-containing monomers capable of homopolymerization and/or
copolymerization with other monomers to give polymers containing
acetal and/or aldehyde groups. It also relates to the preparation
of the aldehyde-containing polymers from the corresponding
acetal-containing polymers. It further relates to the use of the
polymers as crosslinkable coatings, adhesives, and nonwoven
binders.
Blocked aldehydes of unsaturated compounds have been described in
various patents. Most of these relate to dialkyl acetals and
diacetates of aliphatic aldehydes.
U.S. Pat. No. 2,417,404 (issued Mar. 11, 1947 to L. M. Minsk et
al.) and U.S. Pat. No. 2,485,239 (issued Oct. 18, 1949 to E. F.
Izard) describe the preparation and copolymerization of diacetates
of olefinic aldehydes.
U.S. Pat. No. 4,191,838 (issued Mar. 4, 1980 to F. Merger et al.)
describes acrylate and methacrylate esters of
2,2-dimethyl-3-hydroxy-propanaldehyde and U.S. Pat. No. 4,250,070
(issued Feb. 10, 1981 to G. Ley et al.) describe polymers prepared
from these aldehyde-containing monomers. The polymers are cured
(i.e., crosslinked) with hydrazine-containing derivatives which are
known to be toxic.
U.S. Pat. No. 4.663.410 (issued May 5, 1987 to R. K. Pinschmidt,
Jr. et al.) describes blocked aldehyde monomers from aliphatic
amino-aldehydes.
U.S. Pat. No. 4,281,207 (issued Jul. 28, 1981 to J. C. Wilson) and
U.S. Pat. No. 4,225,689 (issued Sep. 30, 1980 to J. C. Wilson et
al.) describe vinyl aryl ethers of aromatic phenolic aldehydes. The
aryl vinyl ethers are derived from vinyl benzyl chloride and a
phenolic aldehyde which is not masked or blocked. This is known to
cause problems during polymerization and copolymerization.
There is a need for crosslinkable acetal-containing polymers and
for aldehyde-containing polymers wherein the method for introducing
the aldehyde groups is not dependent on reaction with an
aldehyde-containing monomer.
SUMMARY OF THE INVENTION
The present invention provides novel acrylate, methacrylate,
acrylamide, and methacrylamide, and diallylammonium halides
monomers which contain aliphatic acetal or aldehyde groups. It also
provides particularly interesting monomers which are prepared by
the esterification of 2,2-dimethyl-3-hydroxy-propanaldehyde with
.alpha.,.beta.-unsaturated acids such as crotonic, maleic, fumaric,
or itaconic acid. The monomers have the general structure ##STR1##
where A and A' are independently a lower alkyl or A and A' together
form at least a 5-membered cyclic acetal. The starting materials
are inexpensive and commercially available and the monomers are
easier to prepare, store, and handle than monomers prepared using
esters of acrylic or methacrylic acid. The latter are known to have
a great propencity to premature homopolymerization and crosslinking
during their preparation. The resulting aldehyde-containing
monomers are converted to the acetals by reaction with an
alcohol.
The present invention also provides novel monomers which contain
aromatic acetal or aldhyde groups and which have the general
structure ##STR2## or Z--Y--X--Ar--CHO, where Z is a polymerizable
group A--Ar is CH.sub.2 --Ar when Y is O, N, or NH, or ##STR3## or
X--Ar is CH.sub.2 --CH.sub.2 --O--Ar or CH.sub.2 --CH(OH)--CH.sub.2
--O--Ar when Y is O Ar is a substituted or unsubstituted divalent
aryl group, and A and A' are as defined above. The term aryl is
intended to include not only conjugated hydrocarbons but also
conjugated heterocyclic systems. They include monomers based on
furfuraldehyde, benzene, or naphathalene which contain aromatic
acetal or aldehyde groups.
The acetal-containing acrylate monomers include
2-(5,5-dimethyl-1,3-dioxan-2-yl)ethyoxyethyl acrylate,
2-(5,5-dimethyl-1,3-dioxan-2-yl)ethyl acrylate, and
1-(5,5-dimethyl-1,3-dioxan-2-yl)propyl acrylate. The
acetal-containing methacrylate monomers include
2[2-(1,3-dioxolan-2-yl)-ethoxy]ethyl methacrylate,
2[2-(1,3-dioxolan-2-yl)-1-methylethoxy]ethyl methacrylate, and
3-[N-methyl, N-(2,2-dimethoxyethyl)amino-2-hydroxypropyl
methacrylate. The acetal-containing acrylamide and methacrylamide
monomers include N-[2-(5,5-dimethyl-1,3-dioxan-2-yl)ethyl
acrylamide and N,N-dimethyl, N-[3-dioxolan-2-yl)
ethoxyethoxy-2-hydroxypropyl methacrylamidopropylammonium chloride.
The acetal-containing N-N-diallylammonium halide monomer is
N-methyl, N-(2,2-dimethoxy)ethyl, N,N-diallylammonium bromide.
Particularly interesting monomers are based on the esters of
.alpha.,.beta.-unsaturated acids. They include
(3,3-dimethoxy-2,2-dimethyl) propyl crotonate,
(3,3-dimethoxy-2,2-dimethyl) propyl fumarate, (3,3
dimethoxy-2,2-dimethyl) propyl maleate,
(3,3-dimethoxy-2,2-dimethyl) propyl itaconate,
bis(3,3-dimethoxy-2,2-dimethyl) propyl fumarate,
bis(3,3-dimethoxy-2,2-dimethyl) propyl maleate, and
bis(3,3-dimethoxy-2,2-dimethyl) propyl itaconate.
The novel monomers which contain aromatic acetal or aldehyde groups
and which have the general structure ##STR4## or Z--Y--X--Ar--CHO
contain furan, benzene, napthalene or similar aromatic groups.
The novel monomers based on furan acetal groups and have the
general structure ##STR5## wherein R' is an ethylenically
unsaturated group and A and A. are independently a lower alkyl or A
and A' together form at least a 5-membered cyclic acetal.
Typical of the acetal-containing monomers are
[5-(dimethoxymethyl)-furfur-2-yl)methyl acrylate and
5-(N,N-di[propyl-1-en-3-]aminomethyl)-2-dimethoxymethyl furan.
Typical of the aldehyde-containing monomers based on furan is
5-(N,N-di[propyl-1-en-3-]aminoethyl)-2-furancarboxyaldehyde.
Typical of the acetal-containing monomers based on benzene are
phenyl (4-dimethoxymethyl)acrylate, phenyl
(2-dimethoxymethyl)acrylate, 2-(2-(dimethoxymethylphenoxy)ethyl
acrylate, 2-(2-[2-(1,3-dioxolano)]phenoxy)ethyl acrylate,
2-hydroxy-3-(4-dimethoxymethylphenoxy)propyl methacrylate, and
4-dimethoxymethyl)naphthyl methacrylate.
The present invention provides acetal-containing homopolymers and
copolymers. The monomer repeating unit in the homopolymer is
derived from one or more of the above ethylenically or allylically
unsaturated monomers containing an acetal group ##STR6## other than
the acetal-containing monomers based on the esters of the
.alpha.,.beta.-unsaturated acids. The monomer repeating units in
the copolymer are derived from one or more ethylenically or
allylically unsaturated monomers containing an acetal group and
from one or more ethylenically or allylically unsaturated monomers
other than the acetal-containing monomer.
The acetal-containing monomers copolymerize very cleanly producing
high molecular weight polymers with minimum precrosslinking. The
polymers which contain acetal groups (often referred to as a
blocked aldehyde groups) can be cured by self-crosslinking or
through a hydroxyl-or amine-functionality introduced as a
comonomer, coreactant, or reactive group present on the substrate
to which the polymer is applied.
The present invention also provides aldehyde-containing
homopolymers or copolymers. Polymerization of the
aldehyde-containing monomers leads to low molecular weight
polymers. The polymers may be crosslinked as described above. In
the homopolymer the monomer repeating unit is derived from one or
more ethylenically or allylically unsaturated monomers containing
an aldehyde group (--CHO). In the copolymer the repeating units are
derived from one or more ethylenically or allylically unsaturated
monomers containing an aldehyde group and one or more ethylenically
or allylically unsaturated monomers other than an
aldehyde-containing monomer.
The practitioner will recognize that the monomer units may be
randomly arranged or arranged alternately or in blocks and will
vary depending upon the polymerization conditions and monomer
reactivity. As used hereafter, the term "polymers" is intended to
include homopolymers and copolymers.
The aldehyde-containing polymers may be prepared by hydrolyzing the
acetal groups in an acetal-containing polymer. The hydrolysis is
carried out at a pH of less than 7, preferably 5 or less, most
preferably 2-4. The polymer can also be prepared by polymerizing an
aldehyde-containing monomer. Direct polymerization, however, is not
recommended.
The polymers containing the aliphatic acetals are useful, for
example, as crosslinkable coatings, adhesives, and nonwoven
binders. Vinyl polymer coatings can be crosslinked by mild acid
catalysis to provide water - and solvent-resistant coatings. The
acetal-containing polymers can be hydrolyzed to aldehyde-containing
polymers and reacted with monomeric dye intermediates containing
aldehyde reactive groups to form polymeric dye intermediates useful
in color photography. The polymers based on the furfuraldehyde
monomers are particularly useful when used in combination with
crosslinking agents such as polyamines. The aldehyde-containing
polymers are useful in the preparation of silver halide dispersions
which have photographic applications.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The acrylate, methacrylate, acrylamide, and methacrylamide monomers
of this invention can be prepared by reaction of acryloyl or
methacryloyl chloride with amine-containing acetals.
The acetal-containing monomers may be prepared in three or more
ways. The first type of reaction is that between an alcohol- or
amino-containing acetal and an acryl or methacryl compound having a
reactive site such as an acryl halide (e.g., acryloyl chloride), an
epoxide (e.g., glycidyl methacrylate), or an isocyanate (e.g.,
isocyanatoethyl methacrylate). The second type of reactions is that
between an alcohol- or amino-containing vinyl monomer and an acetal
having a reactive site such as a chlorohydrin or an epoxide group
(e.g., 2-(glycidyloxyethoxy)ethyl 1,3-dioxolane). The third type of
reactions is that between two moles of an allyl halide and an
amino-containing acetal or between diallylamine and an acetal with
a reactive site such as those above. Styrene derivatives having a
benzylic halide can also be used in preparing acetal-containing
monomers. The acetal-containing monomers can be converted to
aldehyde-containing monomers by treatment with acid at pH of 6 or
less.
In addition to the above methods, a method involving direct
esterification of the corresponding hydroxy-aldehyde with the
.alpha.,.beta.-unsaturated acids (e.g., crotonic, maleic, fumaric,
and itaconic) using a strong mineral acid such as methane sulfonic,
sulfuric, hydrochloric, or Lewis acids such as boron trifluoride,
zinc chloride and the like can be used.
Both the acetal-containing or aldehyde-containing monomers are
useful as polymerizable monomers. They may be used to form
homopolymers or their mixtures may be used to form polymers
thereof. They may also be used to form addition polymers with other
ethylenically unsaturated monomers. The polymers may be prepared by
solution, emulsion, precipitation, suspension, or bulk
polymerization techniques. The preferred method is emulsion
polymerization using a free radical and conventional emulsion
techniques.
The first method involves the reaction of an alcohol-containing
aromatic aldehyde or acetal (e.g.,
5-hydroxymethyl-2-furfuraldehyde) with a polymerizable acid
chloride (e.g., acryloyl chloride). The hydrogen chloride evolved
in the reaction can be scavenged by a non-nucleophilic base (e.g.,
2,4,6-collidine). This reaction can also be run in a two phase
system in which the aqueous phase contains sodium hydroxide and the
organic phase is a non-water miscible solvent (e.g., toluene). The
resulting esters are isolated and purified by distillation. The
second method involves the reaction of an aromatic chloromethyl
aldehyde (e.g., 5-chloromethyl furfuraldehyde) with a polymerizable
amine (e.g., vinyl amine) or polymerizable alcohol (e.g., allyl
alcohol). The reaction is carried out in a non-reactive solvent
(e.g., toluene, tetrahydrofuran, and the like). The reaction
mixture is generally refluxed overnight. Acid scavengers may be
used, but are not necessary. The products may be purified by
distillation before use.
All of the above named monomers are also suitable for graft
polymerization to polysaccharide substrates. The graft
polymerization is described in U.S. Pat. No. 4,866,151 issued Sep.
12, 1989 to J. J. Tsai et al., the disclosure of which is
incorporated herein by reference.
The polymers may be prepared using only the acetal-containing
monomers. However, in some applications where the presence of fewer
aldehyde groups is desirable, other typical comonomers can be used.
These can include ethylenically unsaturated monomers which may
contain anionic or cationic charges.
Suitable monomers include ethylene; styrene and substituted
styrenes such as vinyl toluene, .alpha.-methyl styrene,
chloromethylstyrene, and the like; compounds such as acrylic and
methacrylic acids, or their salts, or their esters such as methyl,
ethyl, butyl, 2-ethylhexyl acrylates and methacrylates; acrylamides
and methacrylamides and their N-substituted derivatives; itaconic
acid and its functional derivatives, preferably the esters; maleic
anhydride; maleic and fumaric acids and their esters; acrylonitrile
and methacrylonitrile; vinyl chloride; vinyl alkanoates, such as
vinyl acetate, vinyl propionate, vinyl neodecanoate, vinyl
pivalate, and the like; vinyl ethers; vinyl pyridine and vinyl
pyrrolidone; vinyl ketones; vinylidene compounds, such as
vinylidene chloride; allylidene compounds such as allylidene
diacetates; conjugated diene monomers such as butadiene-1,3,
isoprene, and chlorobutadiene-1,3; diallylamine and its respective
salts; diallyl dialkyl quaternary ammonium salts;
N,N-dialkylaminoalkyl acrylate and methacrylate and their
respective salts, N,N-dialkylaminoalkyl acrylamide and
methacrylamide and their respective salts; vinylbenzyldialkyl amine
and their respective salts; acids such as vinylsulfonic acid,
styrene sulfonic acid, (meth)acrylamidopropanesulfonic acid and
their respective salts; and the like.
Acrylic or vinyl acrylic polymers useful for preparing
crosslinkable compositions contain about 0.5 to 90%, preferably
about 5 to 30%, of the acetal-containing monomer, about 0.5 to 90%,
preferably about 5 to 30%, of a hydroxy-containing monomer, and
about 9.5 to 99%, preferably about 40 to 90% of other acrylic or
vinyl acrylic monomers. Ethylene vinyl ester polymers useful for
preparing crosslinkable compositions contain about 0.5 to 90%,
preferably about 1 to 20%, of the acetal-containing monomer, about
0.5 to 90%, preferably about 1 to 20%, of the hydroxy-containing
monomer, about 5 to 35% ethylene, and about 65 to 95% vinyl ester.
Suitable hydroxy-containing monomers include 2-hydroxyethyl
acrylate or methacrylate, 2-hydroxypropyl acrylate or methacrylate,
or vinyl alcohol (from the hydrolysis of vinyl acetate). Other
suitable comonomers are discussed above. Particularly preferred are
methyl, ethyl, butyl, and/or 2-ethylhexyl acrylates or
methacrylates; vinyl acetate, vinyl propionate, vinyl neodecanoate,
and/or vinyl pivalate; ethylene; styrene; acrylonitrile and/or
methacrylonitrile; and acrylamide and/or methacrylamide.
The acetal-containing copolymers based on the esters of
.alpha.,.beta.-unsaturated acids are particularly useful as binders
for nonwovens. The corresponding aldehyde-containing polymers are
not preferred for this end use. Suitable nonwovens include pulp,
rayon, and polyester nonwovens.
The starting fibrous web can be formed by any one of the
conventional techniques for depositing or arranging fibers in a web
or layer. These techniques include carding, garnetting, air-laying,
and the like. Individual webs or thin layers formed by one or more
of these techniques can also be lapped or laminated to provide a
thicker layer for conversion into a heavier fabric. In general, the
fibers extend in a plurality of diverse directions in general
alignment with the major plane of the fabric, overlapping,
intersecting and supporting one another to form an open, porous
structure. When reference is made to "cellulose" fibers, those
fibers containing predominately C.sub.6 H.sub.10 O.sub.5 groupings
are meant. Thus, examples of the fibers to be used in the starting
web are the natural cellulose fibers such as wood pulp and
chemically modified celluloses such as regenerated cellulose. Often
the fibrous starting web contains at least 50% cellulose fibers,
whether they be natural or synthetic or a combination thereof.
Other fibers in the starting web may comprise natural fibers such
as wool; artificial fibers such as cellulose acetate; synthetic
fibers such as polyamides (e.g., nylon), polyesters (e.g., "Dynel",
"Acrylan", "Orlon"), "Orlon,"), polyolefins such as polyethylene,
polyvinyl chloride, polyurethane, and the like, alone or in
combination with one another.
The fibrous starting layer or web suitably weighs from about 5 to
65 grams per square yard and generally weighs about 10 to 40 grams
per square yard. This fibrous starting layer, regardless of its
method of preparation, is then subjected to at least one of the
several types of latex bonding operations to anchor the individual
fibers together to form a self-sustaining web. Some of the
better-known methods of bonding are overall impregnation, spraying
or printing the web with intermittent or continuous straight or
wavy lines or areas of binder extending generally transversely or
diagonally across the web and, additionally if desired, along the
web.
The amount of binder, calculated on a dry basis, applied to the
fibrous starting web suitably ranges from about 10 to about 100
parts or more per 100 parts of the starting web, and preferably
from about 20 to about 45 per 100 parts of the starting web. The
impregnated web is then dried and cured. The fabrics are suitably
dried by passing them through an air oven or over a series of
heated cans or the like and then through a curing oven or sections
of hot cans. Ordinarily, convection air drying is effected at
65.degree.-95.degree. C. for 2-6 minutes, followed by curing at
145.degree.-155.degree. C. for 1-5 minutes or more. However, other
time-temperature relationships can be employed, as is well known in
the art, shorter times at higher temperatures or longer times at
lower temperatures being used. For example, the curing step can be
carried out at about 135.degree. C. for about 15 minutes or more in
a laboratory or pilot line but may require only 2 to 20 seconds on
high pressure, high efficiency steam cans used in high speed
production. If desired, the drying and curing can be effected in a
single exposure or step.
Nonwoven fabrics prepared in accordance with this invention have
greater strength than other resin bonded nonwovens of comparable
softness levels and, as such, are competitive with woven fabrics
and thermally bonded polyolefins.
It can be appreciated by the practitioner that a large number of
variations may be effected in preparing selecting the monomers and
comonomers and polymerizing them in accordance with the procedure
described above without materially departing from the scope and
spirit of the invention. Such variations will be evident to those
skilled in the art and are to be included within the scope of the
invention.
In the examples which follow, all parts and percentages are given
by weight and all temperatures are in degrees Celsius unless
otherwise noted.
The chemical structure of the monomers were verified by infrared,
NMR, and/or GC-mass spectral analyses.
EXAMPLE I
This example describes the preparation of novel acetal-containing
acrylate and methacrylate monomers. ##STR7##
A mixture of hydroxyethyl acrylate (11.6 g.), an equivalent amount
of 2-ethylenyl-5,5-dimethyl-1,3-dioxane (EDD) (14.2 g.), and a
catalytic amount of p-toluenesulfonic acid (100 mg.) was heated at
65.degree. C. overnight. Gas chromatography showed the reaction
occurred. The unreacted starting materials were removed at
40.degree. C. under 0.05 mm Hg. ##STR8##
In the presence of a catalytic amount of p-toluenesulfonic acid
(100 mg.) a mixture of acrylic acid (7.20 g., 0.1 mole) and
2-ethylenyl-5,5-dimethyl-1,3-dioxane (14.2 g.) was stirred at
60.degree. C. for 16 hours. Gas chromatography separation (the
column temperature was raised from 50.degree. C. to 200.degree. C.
at a rate of 15.degree. C./minute) showed a major product at 8.40
minutes and some unreacted unsaturated acetal at 1.50 minutes. Both
unreacted starting materials were easily stripped off under vacuum.
##STR9##
2-Propenyl-5,5-dimethyl-1,3-dioxane (PDD) was reacted with acrylic
acid under the same conditions as the reaction with EDD (see
Monomer I-B). ##STR10##
To a 500 ml. four-neck round bottom flask equipped with a
mechanical stirrer, condenser, thermometer and addition funnel were
added initially 22.0 g. triethylamine, 32.4 g.
2-[2(2-hydroxyethoxy)-ethyl]-1,3-dioxolane, and 100 ml. methylene
chloride and then 23.22 g. methacryloyl chloride were added
dropwise. The temperature was reduced to about 0.degree. C. to
-5.degree. C. A total of 24.6 g. methacryloyl chloride was added
dropwise through an addition funnel. While maintaining the
temperature at about 0.degree. to -5.degree. C., the mixture was
then allowed to warm to room temperature and stirred for 30 min.
and added to a equal volume (180 ml.) of ice-water. The methylene
chloride layer was separated from the aqueous layer, a small mount
of anhydrous magnesium sulfate (3 g.) was added, the solution was
filtered, and methylene chloride was stripped off to isolate the
product. Purification was done by as above at 65.2.degree. C. under
0.5 mm. Hg pressure. The monomer was purified by distillation at
106.degree. C. under 0.2 mm Hg pressure. ##STR11##
Following the above procedure, the monomer was prepared using 22 g.
triethylamine, 35.2 g. 2-[2-hydroxyethoxy)propyl]-1,3-dioxolane,
23.22 g. methacryloyl chloride, and 180 ml. methylene chloride. The
product was purified by vacuum distillation at 93.2.degree. C.
under 0.2 mm. Hg pressure. ##STR12##
Glycidyl methacrylate (14.2 g.) was reacted with 11.9 of
methylaminoacetaldehyde dimethyl acetal at 75.degree. C. for 3
hours in the presence of a catalytic amount of tetrabutyl-ammonium
chloride (150 mg.) and a inhibitor (50 mg. of 4-t-butyl cathechol).
Air was passed through the reaction mixture to prevent
polymerization reactions. The product was isolated by vacuum
distillation at 118.degree. C. under 0.05 mm Hg pressure.
EXAMPLE II
This example describes the preparation of novel acetal-containing
acrylamide and methacrylamide monomers. ##STR13##
The product was prepared by reacting the unsaturated acetal (EDD)
with acrylamide using a procedure similar to that described for
monomers I-D. ##STR14##
Dimethylaminopropyl methacrylamide (DMAPMA) was reacted with
2-(glycidyloxyethoxy)ethyl 1,3-dioxolane under acidic conditions to
give the monomer. Thin-layer chromatograph separation showed Rf
0.58, 0.35, and 0.18 for DMAPMA, 2-(glycidyloxyethoxy)ethyl
1,3-dioxolane, and the monomer, respectively (eluant: 50/50
toluene-methanol). The monomer can be purified by column
chromatography.
EXAMPLE III
This example describes the preparation of a N, N-diallyl-ammonium
chloride monomer containing acetal groups. ##STR15##
To a 250 ml. four-neck round bottom flask, equipped as described in
Example I, were added 23.83 g. N-methylacetaldehyde dimethyl acetal
and 25 ml. tetrahydrofuran. Then 24.18 g. allyl bromide were added
slowly. While maintaining the temperature at about 0.degree. C.
After the addition was completed, the temperature was brought to
40.degree. C. and the reaction mixture was stirred for 6 hours. It
was then cooled in 0.degree. C. and 50% aqueous sodium hydroxide
solution (16 g) was added. Then, another equivalent amount of allyl
bromide (24.18 g) was added slowly. The temperature was raised to
50.degree. C. and the reaction mixture was stirred overnight. The
reaction mixture was concentrated on a rotary evaporator. Acetone
(400 ml) was added to the viscous liquid to precipite the inorganic
salt which removed by filtration. The acetone solution was
concentrated on the rotary evaporator to give the final product.
The moisture of this ammonium salt could not be determined
accurately. The ionic bromide was 26.78% (expected 28.52%) and the
organic bromide was 0%.
EXAMPLE IV
This example describes the preparation of novel acetal- and
aldehyde-containing monomers based on crotonic and maleic acid.
##STR16##
This monomer was prepared in two steps. In the first step, 2,
2-dimethyl-3-hydroxy propanaldehyde was esterified with crotonic
acid in the presence of a strong acid. In the second step the
intermediate ethyl (2,2-dimethyl-2-formyl)crotonate (EDFC) was
converted to the monomer by reaction with methanol and trimethyl
orthoformate.
In a 2 l. reaction flask fitted with a mechanical stirrer,
thermometer, Dean-Stark water trap, condenser and a heating mantle
were placed crotonic acid (258 g. 3 mole), 2,2-dimethyl-3-hydroxy
propanaldehyde (204 g., 2 mole), toluene (500 g.), 70%
methanesulfonic acid (41 g., 0.3 mole), and cupric chloride (0.050
g., 0.36 mmol). The reaction mixture was heated to 60.degree. C.
for 2 hours to reflux when the water from the reaction was
azeotroped into the trap. The reaction was continued until no more
water could be azeotroped. A total of 47 g. of water was collected
in 5 hours, indicating that the reaction was essentially complete.
The reaction mixture was cooled, and the excess acid was
neutralized with aqueous sodium hydroxide and washed with water
until the washings were neutral. The toluene solution containing
the product was dried over anhydrous magnesium sulfate and
filtered. Toluene was removed under reduced pressure and the
residue was vacuum distilled (58.degree.-65.degree. C., 0.1 mm Hg)
to obtain 142 g. of pure ethyl(2,2-dimethyl-2-formyl)
crotonate.
The intermediate ethyl (2,2-dimethyl-2-formyl) crotonate was
converted to the dimethyl acetal. To a 1 l. reaction flask fitted
with a mechanical stirrer, thermometer, reflux condenser,
CaCl.sub.2 moisture guard tube and a heating mantle were placed
ethyl (2,2-dimethyl-2-formyl) crotonate (85 g., 0.5 mole), absolute
methanol (150 g.), trimethyl orthoformate (53 g., 0.5 mole) and
crosslinked poly(styrenesulfonic acid) catalyst (2 g.). The
reaction mixture was refluxed for 1 hour. When the reaction was
completed, as monitored by H-1 NMR spectroscopy for the
disappearance of the aldehyde and appearance of the acetal peaks,
the reaction mixture was cooled and the catalyst was filtered off.
The solvent, methanol, and volatile components were removed under
reduced pressure to obtain 103 g. of pure
(3,3-dimethoxy-2,2-dimethyl)propyl crotonate. ##STR17##
The monomer was prepared according to the procedure described above
except that maleic anhydride was used in place of crotonic acid in
the first step and the mole ratio of maleic anhydride to
2,2-dimethyl-3-hydroxy propanaldehyde was 1:2 and of the
intermediate aldehyde to trimethyl orthoformate was also 1:2 in the
second step of this reaction.
EXAMPLE V
Part A
This example describes the preparation of novel aldehyde-containing
and acetal-containing aromatic monomers. ##STR18##
To a 500 ml. four-neck round bottom flask equipped with a
mechanical stirrer, condenser, thermometer, and addition funnel
were added triethylamine (10.3 g.), 2-hydroxymethyl furfural
dimethyl acetal (17.2 g.), and methylene chloride (90 ml.). The
temperature was brought down to 0.degree.-5.degree. C., and
acryloyl chloride (9.23 g.) was added dropwise through an addition
funnel while the temperature was maintained at between 0.degree. C.
and -5.degree. C. After the addition was completed, the bath was
warmed to room temperature and stirred for 30 min. The reaction
mixture was added to an equal volume (90 ml.) of ice-water. The
methylene chloride layer was separated from the aqueous layer in a
separatory funnel. A small amount of anhydrous magnesium sulfate
was added to the methylene chloride solution. The methylene
chloride was filtered and stripped to isolate the product which was
purified by vacuum distillation at 95.degree. C. under 0.5 mm Hg
pressure. ##STR19##
Using the procedure described above chloromethyl furfuraldehyde and
diallylamine were reacted to provide the above monomer.
##STR20##
The above-acetal containing monomer was prepared by treating the
monomer designated V-B with methanol in the presence of a trace
amount of p-toluene sulfonic acid.
Part B
The following aromatic aldehyde- or acetal-containing containing
monomers can be prepared using the above procedure and indicated
reagents. ##STR21##
from chloromethyl furfuraldehyde and allyl amine, followed by
treatment with methanol to convert the aldehyde to the acetal.
EXAMPLE VI
This example describes the preparation of monomers containing
aromatic acetal groups.
Part A ##STR22##
The preparation was carried out in two steps. In the first step 122
g. (1 mole) 4-hydroxybenzaldehyde, 150 g. absolute methanol, 124 g.
(1.2 mole) trimethyl orthoformate and 2.5 g. (0.017 mole)
polyvinylpyridinium hydrochloride (PVP.HCl) (prepared from
polyvinyl pyridine and sold under the trade name Reillex 425) were
added to a 1 1. 4-neck flask equipped with a mechanical stirrer,
condenser, calcium chloride drying tube and a thermometer. The
mixture was heated under reflux (65.degree. C.) for 1 hr. The
solution was cooled and 2 g. (0.019 mole) anhydrous sodium
carbonate were added. The mixture was stirred for 15 min. The
insoluble inorganic salts and the PVP.HCl catalyst were filtered
off under suction. The dimethoxymethyl phenol was isolated by
removing the solvent and other volatile by-products under reduced
pressure using a Rotovap. The residue was kept under a high vacuum
(0.5 torr) for 1 hr. to remove any residual volatile components.
The product was obtained as a light yellow oil. The yield was 98%
(165 g.). The product was characterized by IR and H-.sup.1 NMR. The
IR showed no aldehyde carbonyl band at 1685 cm.sup.-1. The H-1 NMR
showed signals for methoxy methyl at 3.3 ppm but no aldehyde proton
at 10.4 ppm. The purity of the sample was determined to be 96% from
its GC on a carbowax-20M column.
In the second step, 107.5 g. (1.1 moles) triethylamine, 168 g. (1
mole) dimethoxymethyl phenol from the 1st step, and 875 ml.
anhydrous ether were placed in a 3 l. 4-neck flask equipped with
mechanical stirrer, condenser, 250 ml. pressure equalized addition
funnel and thermometer. The solution was cooled to 5.degree. C. in
an ice/salt mixture. A solution of 95 g. (1.05 mole) acryloyl
chloride in anhydrous ether (125 ml.) was placed in the addition
funnel. The acryloyl chloride solution was added at a rate
sufficient to maintain the temperature below 10.degree. C. The
reaction mixture was stirred for an additional 30 min. after the
acryloyl chloride addition was completed. The ice bath was removed
and the reaction mixture was allowed to warm to room temperature.
It was stirred for an additional 2 hr. after which the
triethylamine hydrochloride was filtered off under suction. The
filtrate was washed three times with 150 ml. of 0.1N sodium
hydroxide, washed with water until neutral (pH 6-7), and then
washed twice with 50 ml. of saturated sodium chloride. The ether
layer was dried over anhydrous magnesium sulfate and filtered. The
solvent was removed under reduced pressure. The crude product was
distilled under high vacuum (110.degree. C., 0.1 mm Hg) to obtain
195 g. (88% yield) of the monomer. The monomer was characterized by
H-1 NMR and GC. H-1 NMR taken in CDCl.sub.3 showed peaks at 5.8 and
6.5 ppm for the acrylate protons (3H) in addition to the signals
for DMMP. ##STR23##
The two step preparation was carried out as above using
2-hydroxybenzaldehyde instead of 4-hydroxybenzaldehyde.
##STR24##
The synthesis was carried out in 3 steps. In the first step
2-(2-hydroxyethoxy) benzaldehyde (2-HEBA) was prepared according to
the procedure described by J. Almog, et al. in Tetrahedron, 1981,
37, 3589. In the second step 2-(2-hydroxyethoxy) benzaldehyde
acrylic acid ester was prepared. In the third step the
2-(2-dimethoxymethylphenoxy) ethyl acrylate was prepared.
To a 1 l. round-bottomed flask fitted with a Dean-Stark tube,
mechanical stirrer, thermometer, condenser, and a vented air inlet
were placed 166 g. (1 mole) of the 2-(2-hydroxyethoxy) benzaldehyde
from the first step, 216 g. (3 moles) acrylic acid, 800 ml.
cyclohexane, 9.6 g. (0.1 mole) methane sulfonic acid and 4 g.
(0.008 mole) 4-methoxyphenol. The reaction mixture was heated to
reflux under a slow stream of air and the water azeotrope was
separated at the Dean-Stark trap. The reaction was complete in 4
hr. at which time 19 ml. of aqueous distillate had been collected.
By titration this distillate was found to contain 10% of acrylic
acid.
The reaction mixture was cooled and cyclohexane was distilled off
under reduced pressure (45.degree. C., 160 mm.) followed
by the acrylic acid (50-55.degree. C., 15 mm.). The residue after
distillation was dissolved in 600 ml. ether and washed with 1N
sodium hydroxide until the aqueous washings were distinctly basic
(pH 9 to 10) followed by washing with water until the washings were
neutral. The organic layer was washed with 50 ml. of saturated
sodium chloride and dried over anhydrous sodium sulfate (50 g.).
The ether solution was filtered and the solvent removed under
reduced pressure. The brown oily residue (178 g.) crystallized on
standing. The yield was 81%. The ester was purified by
crystallization from hot cyclohexane (75 ml. per g. of ester). The
white needles had a melting point of 48.degree.-50.degree. C. H-1
NMR taken in CDCl.sub.3 showed signals at ppms 4.4 (m, 4H), 5.8 (m,
1H), 6.3 (m, 2H), 6.9-7.6 (m, 4H) and 10.4 (s 1H).
The dimethyl acetal of the acrylic acid ester from step 2 was
prepared using the procedure described in the first step for the
preparation of phenyl (4-dimethoxymethyl) acrylate (VI-A).
Typically, a reaction of 220 g. (1 mole) of the above acrylate gave
258 g. of a light yellow oil. The product can be further purified
by short path (Kugel Rohr) vacuum distillation (110.degree. C., 0.1
mm Hg). H-1 NMR in CDCl.sub.3 shows signals at ppms 3.4 (s, 1H),
4.4 (m, 4H), 5.7 (s, 1H), 5.9 (m, 1H), 6.3 (m, 2H), 6.9-7.6 (m, 4H)
and no signal at 10.4.
PDMA-2 and PDMA-4 can also be prepared by first making the 2- or
4-formyl phenoxy propenoate by reacting the respective
hydroxybenzaldehydes with acryloyl chloride in the presence of an
acid scavenger similar to step 2 of the PDMA-4 synthesis. The
dimethyl acetal of the 2- or 4-formyl phenoxy acrylate was prepared
using the same procedure described in step 1 of PDMA-4 synthesis.
##STR25##
It was prepared from 2-(2-hydroxyethoxy)benzaldehyde acrylic acid
ester (see Step 2 of 2-DMPEA synthesis).
In a 500-ml. round-bottomed flask fitted with a Dean-Stark trap,
condenser, mechanical stirrer, thermometer, and a heating mantle
was placed 2-(2-formylphenoxy)ethyl acrylate (2-FPEA) (110 g., 0.5
mole), ethylene glycol (47 g., 0.75 mole), cyclohexane (250 ml.)
polystyrene sulfonic acid (Dow M-31 resin) (5 g.), and
4-methoxyphenol (0.05 g.). The reaction mixture was refluxed for 3
hours. When 9 ml. of water was collected, the reaction was
complete.
The reaction mixture was cooled and filtered through a wire mesh to
remove the resin catalyst. The mixture had two phases. The upper
phase containing cyclohexane was discarded. The lower phase was
dissolved in ethyl ether (250 ml.). The ether solution was washed
five times with water (100 ml.) to remove the unreacted glycol and
then washed with a saturated sodium chloride solution. The ether
solution was dried over anhydrous sodium sulfate and filtered. The
solvent was removed under reduced pressure and then under high
vacuum to obtain 120 g. (90% yield) of the monomer. By H-1 NMR
analysis the product showed signals consistent with the structure
shown above. The presence of 5 mol % of unreacted aldehyde
indicated it was 97% pure. ##STR26##
In a 500 ml. 4-neck flask fitted with a mechanical stirrer,
thermometer, condenser and a vented nitrogen bubbler were placed 84
g. (0.5 mol) 4-dimethoxymethyl phenol, 71 g. (0.5 mol) glycidyl
methacrylate (GMA), and 1.5 g. (0.005 mol) benzyltributylammonium
chloride. The apparatus was flushed with air for 5 minutes. The
solution was heated to 80.degree. for 5 hours. The progress of the
reaction was followed by the disappearance of the GMA by GC
analysis of the reaction mixture which indicated 95% reaction. The
solution was cooled and dissolved in 250 ml. of methylene chloride
and washed three times with 1N sodium hydroxide (100 ml.) followed
by water until the washings were neutral. The organic layer was
dried over magnesium sulfate and the solvent was removed at reduced
pressure (Rotovap). The oily residue was dried under high vacuum
for 30 min. to obtain 133 g. (86%) product of the monomer. H-1 NMR
of the product showed signals typical to glycidyl methacrylate
except that the signal for the protons that were attached to the
epoxide carbon at 2.8 and 3.3 ppm showed up as doublets and a
quintet respectively. The spectrum also showed signals for the
4-dimethoxymethyl phenyl group at ppms 7.8-6.9 and 3.4.
##STR27##
The monomer was prepared by the procedure described above starting
with the 2-dimethoxymethyl phenol instead of 4-dimethoxymethyl
phenol.
EXAMPLE VII
This example demonstrates that the aldehyde-containing monomer
designated V-A of Example V can be polymerized. Using standard
emulsion polymerization techniques the monomer was polymerized with
methyl methacrylate (MMA), ethyl acrylate (EA), and 2-hydroxyethyl
acrylate (2-HEA). Sodium persulfate was used as initiator. The
resulting latex had a solids content of 47.1%, Brookfield viscosity
of 60 cps., and pH of 3.1. The polymer of EA/MMA/2-HEA/CHO-monomer
(80.5/4.5/5.5/9.5) was cast as a film. After air-drying the %
insolubles were 81.8%; after drying for 5 min. at 130.degree. C.
the % insolubles were 83.8%.
EXAMPLE VIII
Part A
Acrylic solution polymers containing monomer units derived from
acetal-containing monomers were prepared. The polymer compositions
indicated in Table I were prepared. The acetal-containing monomers
used were those identified as PDMA-4 and PDMA-2 (monomers VI-A and
VI-B) whose preparation is described in Example VI. A comparative
polymer containing the crosslinkable monomer N-methylolacrylamide
(NMA) was also prepared. The PDMA-4 monomer was used at a higher
wt. % than the NMA monomer to maintain the same mole % of
crosslinkable monomers. The polymerizations were carried out in
ethyl alcohol using azoisobutyronitrile as the initiator. The
solids were 38-40%.
Because the polymerization was carried out in alcohol the polymers
obtained were both low molecular weight and had high branching due
to chain transfer to solvent or the PDMA monomer. Alcohol was used
since the NMA monomer used in the comparative polymer is insoluble
in other hydrocarbons.
To determine the crosslinking ability of the polymers films were
cast and cured. The cure was catalyzed with 1% ammonium chloride.
Insolubles were determined in boiling tetrahydrofuran and
filtration was carried out using a Millipore 0.45 micron
filter.
The results show that the polymers containing the acetal-containing
monomers were incorporated into the polymer and were capable of
crosslinking through the acetal even at 5 weight % monomer.
TABLE I
__________________________________________________________________________
Polymerization and Crosslinking of Polymers Containing PDMA-4 and
PDMA-2 A B C D E F G H* Wt Mol Wt Mol Wt Mol Wt Mol Wt Mol Wt Mol
Wt Mol Wt Mol Monomer % % % % % % % % % % % % % % % %
__________________________________________________________________________
EA 71.2 78.3 78.3 84 79.4 8.23 82.0 85.0 79.4 82.4 82 85 85 82.4 77
78.5 MA -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- MMA 4.45
4.83 4.84 5.2 9.8 10.2 10.13 10.5 9.8 10.2 10.1 10.5 10.0 10.2 4.75
4.85 HEA 12.74 11.7 5.8 5.2 5.8 5.1 2.7 2.5 -- -- -- -- -- -- 13.6
11.7 HPA -- -- -- -- -- -- -- -- 5.8 5.1 2.7 2.5 6.0 5.1 -- --
PDMA-4 10.6 5.2 11.1 5.3 4.95 2.4 5.1 2.5 -- -- -- -- -- -- -- --
PDMA-2 -- -- -- -- -- -- -- -- 5.0 2.3 5.1 2.5 2.3 2.3 -- -- NMA --
-- -- -- -- -- -- -- -- -- -- -- -- -- 4.75 4.85 % Insoluble. 94 85
75 77 64 75 80 88
__________________________________________________________________________
*Comparative EA is ethyl acrylate MA is methyl acrylate MMA is
methyl methacrylate HEA is hydroxyethyl acrylate HPA is
hydroxypropyl acrylate PDMA4 is phenyl(4dimethoxymethyl) acrylate
PDMA2 is phenyl(2dimethoxymethyl) acrylate NMA is Nmethylol
acrylamide
EXAMPLE IX
This example describes the preparation of non-woven emulsion
binders.
A 2 l. four-necked round bottom glass flask equipped with a
heating/cooling means, variable rate stirrer and means of metering
monomers and initiators was employed. To the flask were charged 1.0
g. dodecyl benzene sulfonate as a 20% w/w water solution, 3.0 g.
Triton X305 (an alkyl aryl polyethylene oxide with 30 moles
ethylene oxide) as a 70% w/w water solution, 0.5 g. ferrous sulfate
solution as a 1% water solution, and 0.6 g. sodium acetate and 0.1
g. sodium metabisulfate in 420 g. of water. After purging with
nitrogen, 50 g. vinyl acetate and 5 g. butyl acrylate were charged
to the reactor. The contents were then heated to 50.degree. C. The
polymerization was initiated by simultaneously metering in
solutions of 1.5 g. t-butylhydroperoxide and 0.15 g. ammonium
hydroxide in 40 g. water and 1.7 g. sodium metabisulfite and 0.15
g. ammonium hydroperoxide in 40 g. water. The initiators were added
at a uniform rate over a period of 5 hours.
As the initial monomer charge was converted to polymer, the
internal temperature was raised to 62.degree. C. and held for 10
minutes. After seed conversion and a 10 minute hold at 62.degree.
C., polymerization was continued and a pre-emulsified blend of 325
g. vinyl acetate, 120 g. butyl acrylate, 14.8 g. hydroxypropyl
acrylate and 29.6 g. 2-dimethoxymethyl phenoxy ethyl acrylate in a
solution of 12 g. dodecyl benzene sulfonate, 12.68 g. Triton X305
(an alkyl aryl polyethylene oxide with 30 moles ethylene oxide),
and 0.6 g. sodium acetate in 90 g. water was prepared.
The pre-emulsified monomer blend was added at a uniform rate over a
period of 4 hours. The internal temperature was maintained at
62.degree. C. until the polymerization was finished. At the end of
the slow additions, 0.5 g. t-butyl hydroperoxide in 20 g. water was
added uniformly over 5 minutes and the mixture was held for 15
minutes. After the 15 minute hold, the process was repeated with
0.5 g. sodium metabisulfite in 20 g. water. After this procedure
the internal temperature was cooled to 25.degree.-30.degree. C. and
the emulsion was discharged.
All acrylic and styrene/acrylic latex compositions, as well as the
N-methylol acrylamide-containing comparative polymers, were
prepared using the above procedure except for the necessary monomer
modifications.
In the all acrylic latex recipe, 30 g. ethyl acrylate and 20 g.
methyl methacrylate were substituted for the vinyl acetate and
butyl acrylate in the initial charge and 270 g. ethyl acrylate and
180 g. methyl methacrylate were used in the pre-emulsified monomer
blend.
In the styrene/acrylic latex recipe, the initial charge contained
22.5 g. styrene and 27.5 g. butyl acrylate while the pre-emulsified
monomer blend contained 202.5 g. styrene and 247.5 g. butyl
acrylate.
In the control latex recipe, 31.5 g. N-methylol acrylamide (48% w/w
solution in water) were used in the pre-emulsified monomer blend as
a substitute for the acetal-containing monomer
2-(2-dimethoxymethylphenoxy)ethyl acrylate.
Several factors became evident from the results in Table II. First,
the polymers obtained from blocked aldehyde (i.e., the acetal)
monomers (DMPEA-2 and DMDPC) exhibited much better binder
performance than those incorporating the unblocked (i.e., the
aldehyde) monomers (EDFA and EDFC). Second, the acetal-containing
binders show better solvent resistance (MEK tensile) than the
N-methylol acrylamide-containing binders.
The poor performance of the aldehyde-containing polymers is due to
precrosslinking of the polymers from chain transfer to the
aldehyde. This was confirmed from both the intrinsic viscosity (IV)
and % insoluble on the as-is sample of the binder. Polymers from
the acetal-containing monomer (DMDPC) had an intrinsic viscosity in
dimethyl formamide and % insoluble in methylethyl ketone of 1.5 and
0, respectively, whereas polymers from the aldehyde-containing
monomers (EDFA and EDFC) had an intrinsic viscosity and %
insolubles of 1 and 38, respectively.
EXAMPLE X
This example describes the method which would be used to prepare a
pressure sensitive adhesive exhibiting permanent tackiness. The Tg
of the interpolymer should range from +5.degree. to -60.degree.
C.
A 1 l. reactor fitted with a mechanical stirrer, thermometer,
addition funnels, and a reflux condenser is charged with 23.4 g. of
a monomer mixture consisting of 160 g. 2-ethylhexyl acrylate, 40 g.
of methyl acrylate, 20 g. of 2-(2-dimethoxymethylphenoxy)ethyl
acrylate (DMPEA-2), 9 g. 2-hydroxyethyl acrylate and 5 g. of
acrylic acid. The reactor is also charged with 75 g. of a 1:1
mixture of ethyl acetate and hexane along with 0.25 g. of
azobisisobutyronitrile. The reaction mixture is heated to reflux
and held for 15 min. at reflux (72.degree. C.). The remainder of
the monomer mixture and a solution of 2.5 g. azobisisobutyronitrile
in 25 ml. ethyl acetate are added simultaneously via separate
addition funnels over 2 hours. After the addition is complete, the
solution is held at reflux until 99% of the monomers are converted
to polymer. The solution is then cooled to 45.degree. C. and enough
ethyl acetate is added to bring the solids to 45%. The polymer
should have a Mw of 2.5.times.10.sup.5 and the Mn of
3.0.times.10.sup.4.
A 100 g. solution of this polymer is mixed with 2 ml. of a 0.1%
ammonium chloride solution in 90% alcohol, applied to a release
paper, and heated to 100.degree. C. for 3 minutes. It should give a
highly tacky film.
EXAMPLE XI
The following example describes the preparation of a polymer
dispersion of ethylene, vinyl acetate, and the acetal monomer. The
emulsion should be useful as a non-woven binder for pulp,
polyester, or rayon substrates.
A 10 l. stainless steel autoclave reaction vessel equipped with
heating/cooling means, variable rate stirrer and means of metering
monomers and initiators was employed. The reactor was charged with
600 g. Triton X301 (a sodium alkyl aryl polyethylene oxide sulfate
with 3 moles ethylene oxide) as a 20% w/w water solution, 65 g.
Triton X305 (an alkyl aryl polyethylene oxide with 30 moles
ethylene oxide) as a 70% w/w water solution, 35 g. of sodium vinyl
sulfonate as a 25% w/w water solution, 5.0 g. of a 1% water
solution of ferrous sulfate, and 0.5 g. sodium acetate and 2.0 g.
sodium metabisulfite in 1500 g. water. After purging with nitrogen
4000 g. of vinyl acetate were added. The reactor was pressurized to
450 psi with ethylene and equilibrated at 40.degree. C. for 15
minutes. The polymerization was initiated by simultaneously
metering in a solution of 14 g. of tertiary butyl hydroperoxide in
250 g. water and a solution of 28 g. sodium metabisulfite in 300 g.
water. The initiators were added at a uniform rate over a period of
4.5 hours. After initiation occurred (as shown by a 2.degree. C.
increase in temperature), a mixture of 311 g. hydroxypropyl
acrylate, 0.5 g. sodium acetate in 1000 g. water, and 631 g. of
2-(2-dimethoxymethylphenoxy)ethyl acrylate were separately and
simultaneously added at a uniform rate over a period of 3 hours. At
this point the temperature was increased to 65.degree. C. and was
maintained at 65.degree. C. until the polymerization was finished.
At the end of the slow additions, the reactor contents were
transferred to a holding tank and degassed of excess ethylene. To
the holding tank were charged 4.0 g. tertiary butyl hydroperoxide
and 0.45 g. ammonium hydroxide in 40 g. water. After 15 minutes 4
g. of sodium metabisulfite and 0.45 g. ammonium hydroxide in 40 g.
water were also added. After the additions the reaction mixture was
cooled to 25.degree.-30.degree. C. and discharged.
Now that the preferred embodiments of the invention have been in
detail, various modifications and improvements thereon will become
readily apparent to those skilled in the art. Accordingly, the
spirit and scope of the present invention are to be limited only by
the appended claims, and not by the foregoing specification.
__________________________________________________________________________
Tensile Results on Pulp Substrate % Avg. Dry Dry Wet Wet MEK MEK
Pick Basis Peak Peak Peak Peak Peak Peak Up Weight Load Elong Load
Elong Load Elong Vinyl Acrylics Tested (%) (g/sq. yd) (lb.) (%)
(lb.) (%) (lb.) (%)
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75VA/25BA/3HPA/5.9DMPEA-2 12.6 37.6 5.95 4.7 1.64 11.1 1.77 3.6
75VA/25BA/3.9HPA/4.6EDFA* 11.1 37.7 3.78 7.35 0.35 6.94 0.22 2.27
75VA/25BA/3.9HPA/5.0EDFC 11.2 37.9 3.93 7.11 0.29 6.93 0.27 2.58
75VA/25BA/3.9HPA/6.4DMDPC 11.0 37.3 5.24 6.44 1.42 10.53 1.50 4.20
75VA/25BA/3NMA (comparative) 12.2 37.9 5.56 9.00 2.19 13.70 1.00
4.85
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Comparative *This polymer contained the aldehydecontaining monomer
of U.S. Pat. No. 4,250,070. DMPEA2 is
2(2-dimethoxymethylphenoxy)ethyl acrylate DMDPC is
(3,3dimethoxy-2,2-dimethyl)propyl crotonate VA is vinyl acetate BA
is butyl acrylate HPA is hydroxypropy acrylate EDFC is ethyl
(2,2dimethyl-2-formyl) crotonate EDFA is
ethyl(2,2dimethyl-2-formyl) acrylate NMA is Nmethylolacrylamide
TABLE III
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Tensile Evaluation Of All Acrylic Latices With 2-DMPEA Dry Dry Wet
Wet MEK MEK Pick Basis Peak Peak Peak Peak Peak Peak Up Weight Load
Elong Load Elong Load Elong Acrylics Tested (%) (gsy) (lbs.) (5)
(lb.) (%) (lb.) (%)
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Tensile Results on Pulp Substrate 95EA/5MMA/1MAA/2.5NMA
(Comparative) 11.3 38.2 3.71 7.8 2.11 13.7 1.33 4.5
95EA/5MMA/3HEA/6DMPEA-2 11.1 37.5 3.81 5.1 1.47 10.7 2.14 4.6
56BA/44MMA/3NMA (Comparative) 11.7 38.6 5.14 6.8 2.39 11.9 1.21 3.9
56BA/44MMA/3HEA/6DMPEA-2 12.7 38.6 5.43 6.1 1.78 10.6 2.22 4.4
Tensile Results On Polyester Substrate 95EA/5MMA/3HEA/6DMPEA-2 41.9
24.7 0.71 50.2 0.32 27.8 0.04 10.1 95EA/5MMA/1MAA/2.5NMA
(Comparative) 42.3 18.6 1.27 35.8 0.79 23.1 0.34 7.6
56BA/44MMA/3HEA/6DMPEA-2 42.3 17.3 1.11 32.8 0.78 18.6 0.04 8.8
56BA/44MMA/3NMA (Comparative) 40.9 19.4 1.69 30.1 1.38 25.9 0.26
5.9
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EA is ethyl acrylate MMA is methyl methacrylate HEA is hydroxyethyl
acrylate DMPEA is (2,2dimethoxymethylphenoxy)ethyl acrylate NMA is
Nmethylolacrylamide
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